Sales Rank Information
The Sales Rank for an item is displayed on its product information page, a few lines below the image.
The calculation is based entirely on Amazon.co.uk sales and is updated regularly. For example, in the Books shop, the top 10,000 is updated hourly to reflect sales over the preceding 24 hours. The next 100,000 is updated once a day. The rest of the list is updated monthly, based on several different factors.
Our system continually adjusts the Sales Rank of millions of items against each other, so the Sales Rank for an item may change even if its sales remain stable. A change might occur if, for example, an item near it on the list experiences a sudden increase or decrease in sales. Our Sales Rank figures are intended to be of general interest. They are not meant to provide definitive sales information to publishers and manufacturers who, it is assumed, can obtain this information regularly from their distribution sources.